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arXiv · 2412.17893

Duality covariant curvatures for the heterotic string

Falk Hassler·David Osten·Yuho Sakatani
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Abstract

Duality covariant curvature and torsion tensors in double field theory/generalized geometry are central in analyzing consistent truncations, generalized dualities, and related integrable $\sigma$-models. They are constructed systematically with the help of a larger, auxiliary space in a procedure inspired by Cartan geometry originally proposed by Pol\'a\v{c}ek and Siegel for bosonic strings. It pivots around a maximally isotropic group that captures the generalized structure group of the physical space. We show how dropping the isotropy condition on this group allows us to describe heterotic/type I strings. As an immediate application, we construct a new family of heterotic backgrounds that interpolates between the two-dimensional cigar and trumpet backgrounds.

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Falk Hassler, David Osten, Yuho Sakatani. 2024-12-23. Duality covariant curvatures for the heterotic string. https://arxiv.org/abs/2412.17893

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